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Altera_Forum
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15 years ago

IORD_ALTERA_AVALON_PIO_DATA to slow?

Hi, I'm trying to capture samples from an A/D Converter and streaming them onto a PC via an ethernet connection. I've extended the triple speed ethernet design example from the Nios II v9.1 instal...
Altera_Forum's avatar
Altera_Forum
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15 years ago

How does ADC put data on PIO inputs? Is there a clock, latch or strobe signal or this is completely asynchronous to Nios clock?

If data changes asynchronously, it is possible your PIO samples some bits of the previous data word and some bits of the next one, leading to incorrect values. You can't control this because every PIO input can have a slightly different delay and rising/falling time.

You may try multiple sampling, until you get twice the same data.